A man has appeared on Portuguese TV to show off his whopping muscles as part of an 'extreme body' competition.

The bodybuilder known only as 'Valdir' explained how he was fed up with people joking about how thin he was, and so he decided to bulk up.

However Valdir's inflated pecs, traps and biceps have come under fire from viewers, with many accusing him of using a dangerous muscle-enhancing drug.

A man - known only as Valdir - has appeared on a Portuguese TV show, flexing his 'extreme' muscles

The man explained how he decided to transform his body in response to taunts over how thin he was

His bulging biceps do appear out of proportion with other parts of his body, leaving many viewers speculating.

In the short segment, which appeared on Portuguese TV show A Transformação Mais Incrível (which roughly translates as 'amazing transformations'), Valdir makes his muscles dance at the request of the host, and shares his reasons for wanting to transform.

According to YouTube commentators, who translated for English-speaking audiences, Valdir reportedly said that he is very happy and proud of his body.